Absolute alcohol and the process of making the same



UNITED STATES PATENT Bo Drawing.

the Government, or by any other person in i the United'States, without payment of any r0 alty thereon.

his invention relates to a process for making commercial absolute and absolute alcohol whereby all water may be removed from common commercial alcohol.

Up to the beginning of the last century,

alcohol containing more than 95% was unknown. This was and is now the purest alcohol obtainable by the most "perfect Coffey still. When it was found that alcohol could be prepared containing more than 95% alcohol and less than. 5% of water,

the newly prepared product was called abnected with a. second condenser and the solute alcohol. Therefore. absolute alcohol came to mean an alcohol containing lessthan Later, the percentage of 5% of water. water was lowered and Q8-99% alcohol was produced and called absolute alcohol but' soon this term had to be changed to com-- mercial absolute; alcohol when alcohol 99.8% pure wasproduced which is today called absolute? alcohol. However, the

absolute alcohol referred to as being pro duced by the herein-described process is 100% pure.

It is well knownfthat when common alcohol is treated with some dehydrating reagent as anhydrous copper sulfate, calcium chlorid or! quicklime, the water in the alcohol is absorbed by the reagent and by sepa- 1 rating the partially dehydrated alcohol from the reagent and distilling an alcohol of higher purity than 95% is obtained.

Anhy rous copper sulfate and'calcium chlorid are not satisfactory as they do not remove all the water and occasion considerable loss. Quicklime, although it of the large proportion of lime necessary to completely dehydrate the alcohol.

' hydrated alcohol.

' cegttracw of water.

. h at approximately theclave retortcontaini'n formed by thewater 1n the valcoho .eom- 1 -.binin with the quicklime'and unchanged 7 J Iquickime. Before reacting to' the condenser, however, the alcohol vapors pass] 'ves through a vertical drum, which drum is satisfactory results, re uires time an entails considerable loss 0 alcohol on accour'itf 1 Specification of Letters Patent. Patented Aug, 17, 1920, Application med December 20, 1918. Serial No. 207,678.

My discovery embodies'three steps which i with modifications are as follows:

The first step involves the removal of half or two-thlrds of the water by a so called salting out process depending upon the factthat certain salts, or mixtures of salts, l1ke potassium fluorid and potassium carbonate, absorb water and when. added to common alcohol and allowed to stand for some little time, form a layer at the bottom of the receptacle consisting chiefly of salt and water and leave the partiall dehydrated alcohol in the top layer; ot asslum fluorid can not be used alone on account of the fact that it h drolyzes, and

causes considerable loss. ith an appre c able :proportion' of potassium carbonate present, however, this difiiculty is practh cally eliminated.

This step is carried out in a retort providedwith a stirrer'and steam jacket for heating and distillin off the partially dehen this is complete" and the alcohol is practicall all distilled off, the process is stopped, .t e retort con-.,

treating continued with constant stirri until the last traces of'wate'r are distill e off and the salt mixture is dried and granu' lated and ready to .be, used over again.

'Alco hol thus prepared will, usually. .pas's" speclfications for the so called comi'rifercial clave retort similar to the onegused :in. the

first step for a short time, approximately a one hour. This treatment removes allerre third step involves the dlstillation jq mentioned, of the al co the lime h drate underthe pressure of approximately 55 lbs. per square inch, connecting theretort with the condenser. .and containing granu.-' I ilated calciumjcarb d By bringing the-aloe. V

Ipressure heretofore:

o1 from the autohol vapors in contact with the carbid the last traces of water are removed and an alcohol of practically 100% is obtained. Owing to the remarkable hygroscopicity of absolute alcohol the greatest precautions are necessary in order to keep it from absorbing water. Tra s filled with quicklime are necessary in or er to keep it from absorbing moisture vfrom the a1r during the process of distillation.

I have beenjable by my process, to prepare absolute alcohol -without difiicult which gave all tests for 100% pure alcoho -It should be stated that the mixture of the twosalts, potassium carbonate and potassium fluorid is unique in its dehydratlng power. Both salts are powerful dehydrants and the mixture seems to be doub y active on this account. I claim, therefore,

that thesalting out properties of this mixture are new and novel and that no other mixture known will act as it does.

Havin therefore described my process what I c aim is as follows:

1. A process for the preparation of absolute alcohol consistingin treating common commercial alcohol with a mixture of potassium carbonate and potassium fluorid so as to remove some of the water, decanting the alcohol, then heating in an autoclave retort under a pressure of approximately pounds per square inch with quicklime until all but a trace of water has been. removed and finally distilling and passing the vapor formed bydistillat on over calcium carbid whereby the last traceof water is removed.

2. A process of preparing absolute aloe-- hol consisting in treating common commercial alcohol with a mixture of dehydrating salts, decanting :the alcohol, heating .the

partially dehydrated alcohol in an autoclave retort with quicklime and finally dis- .through calcium carbide tilling the alcohol and passing the vapor formed by distillation through calcium carbid.

' 3. ,A process of preparing absolute alco- -hol consisting in heating common commercial alcohol with a mixture of dehydrating salts, decanting the alcohol, heating the partially dehydrated alcohol in an autoclave 5. A process of preparing absolute alcohol consisting in treating common commer-- cial alcohol with a mixture of dehydratin salts which is soluble, alkaline and has salt ing out properties, removing the partly ,de-

to dehydrating f hydrated alcohol, then heating the alcohol in an autoclave retort withquicklime and finally distillin the alcohol and passing the vapor formed cium carbid.

6. A process of preparing absolute alcohol consisting in treating common commercial alcohol with a mixture of dehydrating salts which is soluble, alkaline and has salting out properties, removing the partially dehydrated alcohol, then heating the alcohol in an autoclave retort with quicklime, under a pressure of approximately 55 y distillation through calpounds per square inch and finally distilling the alcohol and passing the vapor formed by distillation through calcium carbid.

varbiter BELL rnmxrosrra. 

